Spray nozzle assemblies are known, such as shown in U.S. Pat. No. 5,275,340 assigned to the same assignee as the present invention, that include a deflector flange which enhances liquid particle breakdown and directs the spray pattern in a transverse direction. Such spray nozzles do not necessarily require pressurized air pre-atomization of the liquid flow stream. These spray nozzles have particular utility in spraying agricultural chemicals because they do not generate extremely fine liquid particles. Nozzles that produce extremely fine liquid particles are generally unsuited for agricultural applications because the discharging spray can be subject to undesirable drifting. Nevertheless, even with nozzles specifically designed for agricultural applications it can be difficult to effect complete coverage of a crop canopy by the downwardly directing spray because the spray often has difficulty achieving good penetration of the crop canopy.